the cause of water ingress for any tank and to
monitor for the reoccurrence of water ingress
once water has been removed from a tank.
The accumulation of water in an underground
fuel tank is usually due to issues with
the fill cap or corrosion of the swing joint at the
vent riser and not an indicator of a breach of
the integrity of the tank shell.
The inspection of below ground tanks for the
presence of water is a good component of an
fuel company’s maintenance program as it is
integral to maintaining fuel quality and to the
reduction of service issues that arise from the
water contributing to the formation of sludge.
Any time the presence of water is identified
in a fuel tank regardless of location; it is
important that the customer is notified.
Any water found during an inspection should
be removed as quickly as possible to minimize
the damage to the tank, the filter, the fuel pump
and the system. Any water and sludge removed
must be disposed of properly. Remember,
removing the water is just the first step in a
process—find out where the water is coming
from and take action to prevent the situation
from reoccurring.
sti-P3 Tanks
In addition to periodically checking for
and removing water in the tank, the anodes
installed on sti-P3 tanks must be tested upon
installation and in three-year intervals. The
test can be performed quite easily by trained
individuals. A list of individuals certified to
perform this test is maintained by the Steel
Tank Institute to aid tank owners in locating
qualified testers.
40 National Oilheat Research Alliance
Cleaning
There is no clear consensus regarding if
and/or when fuel tanks should be “cleaned.”
Condensation, sludge and rust accumulate in
tanks and cause serious operational problems,
yet, the debate continues on the best means to
address these problems.
Some industry professionals believe that
tanks should never be cleaned. Concerns are
that tank cleaning may cause damage to the
tank, that the cleaning process is inadequate
to remove the sediments, the cleaning fails
to eradicate the microorganisms or that tank
cleaning entails expense and sacrifices clean
fuel.
While a major advantage of having tanks
cleaned is that the cleaning process usually
does a very good job of removing the water
that accumulates in tank bottoms; the jury is
still out on just how good a job can be done to
remove the sludge that accumulates on tank
walls. Most fuel tanks don’t have openings
that are large enough to facilitate a thorough
inspection of the tank’s interior. With that said,
cleaning a problem tank normally won’t hurt
the situation and getting the accumulated water
out of the tank offers many advantages that
justify the cost.
Some fuel companies routinely clean their
customer’s problem tanks and then treat them
with an additive to help prevent clogged oil
lines, filters, pump strainers and nozzles and to
reduce the resumption of microbial activity.
For information on tank cleaning systems
visit the following websites:
HamcoTanksystems.com
velcon.com